Fluorescent lamp



Ju1y26,1949, 'EBHUFF `2,477,456

FLUORESGENT LAMP Filed Aug. 29, 1946 Patented July 26, 1949 'TI-Il)WATENT fOfFiFilfCiE p 7iii'mronrfsClim:'mnu-P .fEveife'ttBnHufL SanFrancisco, YCalif. application angustias, 19r6,^seriaiiNo.t93;rr2

"Thejfpresent invention relatesto improvements in *fluorescent Zlamps,and its principal obj'e'ctis to 'provide meansforfecononiicallyoperating a relatively lhigh-vltage` fluorescent vlamp"on a direct current btairredfrom'aseries *cif'dryicells f 7For thispurpose fit is particularly "proposed to Iusewtwo different `yvoltages`.for 'starting "and'for operating atneuanip, arelativ'ly tirrt/"volta'ge*ijeing used "for starting the lamp, rand a higher voltage for'continuing the 'operation of "the glamp.

1 '"Thefus'e 'of Fa relatfvelylow voltage for 'starting the tlamp is 'ofparticular 'advantage "insofar .as it lengthens `the Ylife of thefilament, since 'a higher 'voitagewould "tend to burn out the nla mentin ashortstime. i

i The use of a'higher voltage for continuing the operation :of itlrelampnasthefadvan-t'age of reu ducing the amperage needed fiorfoperatirig the lamp and :thereby extends the .life tof the battery ofdry cells. It'has the further advantage of increasing the tensionbetween the electrodes so as ft'o make it f possible -to 'start *the"lamp by Ierrerginingfoneieiectrodeonly.

ift is -rurther -proposed -in fthe present invention teiprovi-dex'efsimple 'meansfor-stopping 'operation of ithe j'-lai'rip whichiconsists `=.in *the snnple i'expeiiierit of Lmomentarily loy-flassingthe Ianrp current.

``land "finality, Ait is proposed to 'provide certain structuralfeatures and electrical connections whereby the lamp and the electricaloperating means are combined into a simple, attractive and portableunit.

Further objects and advantages of my invention will appear as thespecification proceeds and the new and useful features of the same willbe fully defined in the claims attached hereto.

The preferred form of my invention is illustrated in the accompanyingdrawing forming part of this application, in which:

Figure 1 shows a side `view of my assembled fiuorescent lamp assembledin a portable unit;

Figure 2, a top plan view of a plate carrying Vthe various electricalconnections;

Figure 3, a bottom plan view of the same; and

Figure 4, illustrating a wiring diagram.

AWhile I have shown only the preferred form of my invention, it shouldbe understood that various changes or modifications may be made withinthe scope of the claims attached hereto without departing from thespirit of the invention.

Referring to the drawing in detail, my invention comprises in itsprincipal features a box I containing a series of batteries, a plate 2superi 2 imposed nnftheieox "for marrying itheivarious eleotricalconnections, and a fluorescent itiilfe f3 mounted abovetheiplate.

'The iiuores'ceri-t *tube is-fof commercialstandard type, one 'orfineobjects= of Ethe iinven't'ron being to make a relatively largetu'b'e availalleifor fopera @My iinvention was particmarly feevelopelfin connection with a standard fouiiteenfor twenty watt tube.tourt'eenliinehes long and foire:andronel haifindhes indi-ernster.

'The box Icontain'sa `st-nies of '-'iryfolls 'meren 'abi-y arranged iinthree emits il, i5 enti yt connected in series by Vconductors "l andiBB, ithe first itwo unites and 5 havingfavltageof `forty-*five'voltseach, making a total "of ninety volts, 'and the third caff-ying sixtyvolts, :so that the aggregate voltage sis fone ihnniireu Vand dirty1voi'ts.

The fpositi've terminal iIfi) o'f theisecontl hattery Sj'connects,through-mrow 'and thron'gh'onetsioe 'lf2 for a 'singlespole 1doublethrow'switch ifs, with one Lelectronesfor L'firanre'rt lil 'Lo'f`tlnel'tiibe, latter is 1connesteii to *the negative "terminal Ilorbatteryfl. l

Thus, upon a momentary closing 'o'f Ltheswith at jf2, Ta ommen-twillflowthrongh fth'e 'filament I4, under pressure of ninety volts,energizing the lament. This is the starting circuit.

The positive terminal I6 of battery 6 is connected, through wire I'I, aresistance I8 of preferably fifteen hundred ohms, electrode I9 of thetube, the gas in the tube, and electrode I4 to the negative terminal I5of battery 4.

This is the operating circuit for lighting the tube, and operates on onehundred and fty volts.

This relatively high voltage is sufficient to bridge the gap between thetwo electrodes on the energizing of only one of them, and I have foundfrom experience that it will operate a standard fourteen watt tube,fourteen inches in length and one and one-half inches in diameter, witha resistance of fteen hundred ohms included in the circuit, at a currentconsumption `of approximately forty milliamperes, which insures a longlife for the battery.

For extinguishing the light, I use a shunt or by-pass 20 across the twoelectrodes I9 and I4, the by-pass including the other side ZI of thedouble-throw switch I3, so that, upon momentary closing of the switch at2|, the current of the main operating circuit is made to by-pass thetube. By the time the switch I3 opens again,

the tube has become inoperative for carrying current and will remaininactive until started again by operation of the switch at I2.

The physical arrangement of the wiring system is illustrated in Figures1, 2 and 3. The plate 2, which is of insulating material, and whichpreferably is rectangular in form and slightly larger than the box I, ismounted on top of the latter, in slightly spaced relation thereto, andis anchored inplace by means of two screws 22.

Connection with the battery terminals is made through a conventional,centrally located prong and socket arrangement, in which the positiveterminals I6 and I 0, and the negative terminal Y i5 are represented asshown.

The switch I3 is shown in the form 'of a leaf spring 23 disposedunderneath the plate and centrally anchored thereto, as at 24. The twofree ends of the leaf spring are operated by means of push buttons 25-26slidable in the plate for cooperation with the contacts I2 and 2|respectively.

The starting circuit may be traced as `comprising the battery terminal I(90 volts), the wire II, switch contact I2, switch post 24, wire 21, thefilament at the right end of the tube, the wire 28 back to'batteryterminal I5. This circuit is closed by momentary pressure on the switchbutton 25.

The main circuit comprises the battery terminal I6 (150 volts), wire I1including the resistancek I8, the two electrodes I9'and I4 of the tube,and wire 28 leading back to the negative terminal I of the battery. v

The. by-pass connects the left-hand Yelectrode I9 through wire 20,contact 2|, leaf spring 23 of the switch and wire 21 with the negativeterminal of the battery. This by-pass is closed by operation of switchbutton 26.r Y

The tube 3 is mounted Vin two brackets 30 rising from the ends of theplate, the brackets being of conventional type and suitably equipped forbringing the tub electrodes into the circuit.

The operation of my device is very simple. For starting, the operatormomentarily presses down on button 25 which energzes lament I4 at ninetyvolts and starts the lighting at one hundred ity volts.

For turning oi the light, the operator momentarily presses down onbutton 26 which bypasses the current and automatically extinguishes thelight.

I claim:

1. In a iluorescent gas discharge system, a battery comrising aplurality of cells connected in series, a fluorescent tube having ananode and a lamentary emissive cathode, a starting circuit comprisingunloaded wires connecting the cathode to lowland high sides of the.battery respectively for preheating the cathode and a switch in thecircuit, means independent of the starting circuit connecting the anodeand the cathode to the battery to form a circuit for lighting the tubeautomatically subsequent to the preheating of the cathode, a resistancein said circuit, a shunt for the tube and made to connect theresistance, the anode and the cathode in series fwith the battery, and aswitch in the shunt operable for momentary closing, the shunt havingsufficient conductivity to by-pass current from the tube forextinguishing the latter, and the total resistance of the shunt circuitbeing suicient to prevent'heating of the cathode effective for startingpurposes.

2. A iluorescent gas discharge system as dened in claim 1, in whichthebattery has a pressure of approximately 150 volts,v the tube acapacity of approximately between 14 and 20 watts and the resistanceisvof the value. of approximately 1500 ohms, While the starting circuit.is connected to the battery atl a pressure of approximately volts. A v

EVERETT B. HUFF.

REFERENCES v.CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS VBeck Dec. 31, 1946

